Gael eumpff



UNITED STATES PATENT OFFICE.

CARL RUMPFF, OF APRATH, NEAR ELBERFELD', PRUSSIA, GERMANY.

MANUFACTURE OF DYE-STUFF OR COLORING-MATTER.

SPECIFICATION forming part of Letters Patent No. 256,378, dated April 11, 1882.

Application filed January 9, 1882. (No specimens.)

T 0 all whom it may concern:

Be it known that I, CARL RUMPFF, residing at Aprath, near Elberfeld, in the Kingdom of Prussia and Empire of Germany, haveinvented a new and useful Improvement in the Mannfacture of Dye-Stuffs or Coloring-Matters, of which the following is a specification.

Myinvention relates toa newdye-stufi' which results from the reaction of diazoazo -xylolmonosulphonic acid with the soda salt of my alpha-monosulphonic acid of beta-naphthol.

The preparation and properties of my alphamonosulphonic acid of beta-naphthol, and also of its sodium salt, are described in my application for patent filed April 8, 1881.

I prepare my new dye-stuff as follows: I dissolve one hundred kilograms of finely-powdered amidoazo-xylol-monosulphonic acid in one thousand liters of water. To this solution I add seventy-five kilograms of hydrochloric acid of 21 Baum. I cool the mixture so prepared to from 3 centigrade to 6 centi grade, and then pour into it slowly a solution oftwenty-five kilograms of sodium nitrite in one hun-.

dred kilograms of water.- The mixture is now left at rest for several hours, when the desired chemical reaction will be complete-thatis to say, the amidoazo-xylol-monosulphonic acid will be transformed into the diazoazo-xylolmonosulphonic acid. In the next operation I slowly pour the mixture containing the diazoazo-xylol-monosulphonic acid into a solution of one hundred and fifty kilograms of the sodium salt of my alpha-monosnlphouic acid of beta-naphthol (crystallized from an alcohol so- 35 lution) in one hundred kilograms of ammonia of ten per cent. strength. My new coloringmatter is the result of the reaction of the substances in solution. The following equation New coloring-m atter.

The new dyc-stufi is to be precipitated out 55 of its solution by common salt and purified by crystallization from water.

I claim-- As a new product, the dye stufl or coloringmatter which results from the reaction of di- 60 azoazo-xylol-monosulphonic acid with the sodium salt of the alphamonosulphonic acid of beta-naphthol, substantially as described.

CARL RUMPEF.

Witnesses J. FERD. KEDENBURG,

FR. IT. SCHULTER. 

